Data communication using binary signals takes place at high rates in various applications. For example, in optical data systems, data transmission rates of 155 Mb/s and higher are utilized. In such binary data communication systems a receiver is used for receiving the binary signals from a transmitter. In many cases, the signals received are of a low level and are accompanied by noise. The true binary nature of a distinct rectangular pulse, usually designating a binary 1, sometimes can be partly obscured by noise and result in data errors that adversely affect signal processing equipment to which the output of the receiver is applied.
To improve the ability to accurately recapture the binary signals passing through the receiver before being supplied to other equipment, a slicing technique is employed. This involves slicing the received binary signal at a level about the midpoint of its amplitude, that is, between its maximum and minimum values. The portion of the received binary signal appearing above the slicing level corresponds to a binary 1 and the portion below the slicing level corresponds to a binary 0.
In one type of prior art slicer circuit, the slicing level is varied so as to be at the midpoint of the amplitude of the binary signal. This gives rise to problems in that there can be a variation of the slicing level from the desired midpoint value due to the shifting of the amplitude and reference level of the received signal and operational factors of the receiver itself. Therefore, a need exists to provide a slicing circuit in which the midpoint slicing level of the received signal is more accurately determined and maintained.